Malicious PDF — malware analysis report

Static analysis result for SHA-256 719589c3c3a80e79…

MALICIOUS

PDF

72.6 KB Created: 2021-09-13 00:58:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: a4a3456a645b038130e04509344afa88 SHA-1: 3b95fedd94a502f45eb85083071d366d75a57e59 SHA-256: 719589c3c3a80e7916177d0f77693991889f54b2cc102e812a6357a6d15f80f0
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also contains numerous external URIs, with one heuristic identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery via the embedded JavaScript and external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://bursaceyizgelinlik.com/images_upload/files/1735668310.pdf In PDF document text
    • https://discovercefalu.it/_data/images/file/32263194940.pdfIn PDF document text
    • http://energcomb.net/cms_enercomb/sgi_userfiles/userfiles/files/derotele.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/kabikalizoraw.pdfIn PDF document text
    • http://vngo-cc.vn/cooker/public/files/maxapirulaje.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/53704489802.pdfIn PDF document text
    • http://swaminarayangm.org/userfiles/file/mibowotipufaxo.pdfIn PDF document text
    • http://mictrogiang.com/userfiles/files/79322937152.pdfIn PDF document text
    • https://memorybg.net/app/templates/js/ckfinder/userfiles/files/579262256.pdfIn PDF document text
    • http://matchedtubes.de/userfiles/file/tuvikatemoxowaboza.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/dapakaxut.pdfIn PDF document text
    • http://trivio.it/userfiles/files/fitotorapuginafumos.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/xogapesazixaleliwebemogu.pdfIn PDF document text
    • http://lustigersteirer.at/userfiles/file/wafisirogosipatiwido.pdfIn PDF document text
    • https://castilloexterior.es/ckfinder/userfiles/files/57731896448.pdfIn PDF document text
    • https://umutfm.com/resimler/files/96326093061.pdfIn PDF document text
    • http://thcscatquea.hoaiduc.edu.vn/ckfinder/userfiles/files/19843881848.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/d8c72cf8151dac9d8dd0eb9f28f56788/xanepojiwajuzalizida.pdfIn PDF document text
    • https://0922.sproname.com/files/userfiles/files/mafoxok.pdfIn PDF document text
    • https://pikhospital.com/ck_uploads/uploads/files/66802455012.pdfIn PDF document text
    • https://careerroots.net/ckfinder/userfiles/files/numowudogek.pdfIn PDF document text
    • http://tubesealer.com/uploaded/file/3116236386138257760643.pdfIn PDF document text
    • http://newtrichur.com/userfiles/file/lovajisejinegadifati.pdfIn PDF document text
    • https://www.ijmsir.com/ckfinder/userfiles/files/28654495893.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=how+to+turn+on+mms+messaging+androidPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b94f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB94F 16824 bytes
SHA-256: 683bd4683116200e92c8d87f8cf6e4dd18400ddda313c3ece609fc7e409afb87
font_01_sfnt_off0000e3e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3E4 10724 bytes
SHA-256: 4378685d52c67c5d92831a37f5abb9ad9617185acbf2bcc8e97cd94c630c3c70
font_02_sfnt_off0000fc58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC58 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1